1. Technical Field
The embodiments described herein relate to a semiconductor integrated circuit (IC) and more particularly, to a semiconductor IC that generates a column strobe signal.
2. Related Art
In general, when a column series command is input to a semiconductor IC, i.e., an external command is a read or write command, a column strobe signal is generated for each bank in response to the read or write command. Specifically, when a read or write command is input, for each bank block, a column strobe signal for each bank that activates a corresponding bank is generated for each bank block. Accordingly, each circuit unit is needed to generate the column strobe signal for each bank. Thus, a circuit unit that provides a column series command signal and a circuit unit that provides bank information may be needed.
Recently, due to high integration and a high-speed operation of semiconductor ICs, the number of banks have increased, whereby the number of column strobe signals that control individual banks have also increased. Accordingly, the size of a column strobe signal circuit unit has increased.
In general, the column strobe signal circuit unit is disposed in a peripheral circuit unit. Accordingly, columns strobe signals are transmitted through global lines that function as common signal lines between the peripheral circuit unit and the banks. Thus, the number of column strobe signals increases when the number of banks increases, which results in lowering area efficiency of the semiconductor IC.
In a column strobe signal generating block for each bank, bank address information is needed to activate any one of the banks, and a column command signal that is activated in response to a column series command is needed. Accordingly, the peripheral circuit unit generates bank decoding addresses and a column command signal and transmits the bank decoding addresses and the column command signal to each of the blocks, thereby generating the column strobe signal for each bank. Alternatively, the column strobe signal is commonly transmitted to all banks using the decoded bank address and the column series command signal. Here, if the number of banks increases, the number of bank addresses increases, which results in increasing the number of bank decoding address signals, which are needed to be commonly provided to all of the quarter blocks, or the number of column strobe signals corresponding to the number of banks. Accordingly, since the above-described signals need to be provided from the peripheral circuit unit B to the core circuit unit A, the signals are provided as global line signals, which require long loading time. Moreover, since the number of column strobe signal lines that are disposed in the peripheral circuit unit increases when the number of banks increases, area efficiency of the peripheral circuit unit is lowered.